306 



ORNITHOLOGICAL EXPLORATIONS. 



between the two Japanese specimeos and ^'o. 92557* shot atPetropaul- 

 ski on the last day of September, 1883, the dimensions of which are 

 given below. It is superior in size to the smaller of the Japanese birds, 

 while its color is of exactly the same yellowish shade, and the length 

 of the first primary is considerably [2.6^^] greater than the maximum 

 length of the same portion of the quill in the young horealis. 



My reasons for referring this single specimen to the Japanese species 

 may be clearly seen from the above statements without further comment. 

 But the question presents itself whether there is no intergradation be- 

 tween the two forms. The dimensions certainly intergrade, but not 

 having seen or heard of intermediately colored forms I abstain from 

 naming the present bird Fh. horealis xanthodryas. 



Dimensions of the specimen collected. 



Table of dimennons of specimens from Japan. 



Only one specimen was obtained in the neighborhood of Petropaul- 

 ski, the species thus presumably being scarce. It was the last Willow- 

 warbler I saw during the autumn of 1883. 



« The yellow color of these birds is of a very different tint from that of the young 

 horealis, being of a clear yellow, suffused with greenish, while in the latter t^e jellow 

 is duller and tiuged with buff. It may perhaps not be unnecessary to state that JNo. 

 9^557 is not a bird of the year. 



